first import of dhwk.

[raggedstone] / heartbeat / source / pcipargen.v

//\r
//                  PCI Parity Generator.\r
//\r
// PCI Target generates PAR in the data phase of a read cycle. \r
// The 1's sum on AD, CBE and PAR is even.\r
//\r
//   Date 		  Version	Author	Description\r
//   2005-05-13   R00A00	PAU		First alfa revision	(eng)\r
//\r
//  Copyright (C) 2005 Peio Azkarate, peio@opencores.org\r
//\r
//   This source file is free software; you can redistribute it     |\r
//   and/or modify it under the terms of the GNU Lesser General     |\r
//   Public License as published by the Free Software Foundation;   |\r
//   either version 2.1 of the License, or (at your option) any     |\r
//   later version.                                                 |\r
\r
\r
module pcipargen_new (clk_i, pcidatout_i, cbe_i, parOE_i, par_o);\r
\r
	input clk_i;\r
	input [31:0] pcidatout_i;\r
	input [3:0] cbe_i;\r
	input parOE_i;\r
	output par_o;\r
\r
\r
  	wire [31:0] d;\r
  	wire pardat;\r
  	wire parcbe;\r
  	wire par;\r
  	wire par_s;\r
\r
	assign d = pcidatout_i;\r
\r
	assign pardat = d[0]  ^ d[1]  ^ d[2]  ^ d[3]  ^ d[4]  ^ d[5]  ^ d[6]  ^ d[7]  ^ \r
			   d[8]  ^ d[9]  ^ d[10] ^ d[11] ^ d[12] ^ d[13] ^ d[14] ^ d[15] ^ \r
			   d[16] ^ d[17] ^ d[18] ^ d[19] ^ d[20] ^ d[21] ^ d[22] ^ d[23] ^ \r
			   d[24] ^ d[25] ^ d[26] ^ d[27] ^ d[28] ^ d[29] ^ d[30] ^ d[31];\r
						\r
	assign parcbe = cbe_i[0] ^ cbe_i[1] ^ cbe_i[2] ^ cbe_i[3]; \r
\r
	assign par = pardat ^ parcbe;\r
\r
    // PAR\r
	assign par_o = ( parOE_i == 1 ) ? par_s : 1'bZ;\r
\r
endmodule\r
/*\r
component sync\r
port (\r
    clk             : in std_logic;\r
    d           : in std_logic;\r
    q               : out std_logic\r
);\r
end component;\r
\r
component sync2\r
port (\r
    clk             : in std_logic;\r
    d           : in std_logic;\r
    q               : out std_logic\r
);\r
end component;\r
\r
begin\r
\r
\r
\r
    u1: sync2 port map (\r
		clk => clk_i,\r
		d => par,\r
		q => par_s\r
	);\r
	\r
\r
\r
\r
end rtl;\r
*/\r